Improvement in electric clocks



R. J. SHEEHY.

ELECTRIC-amori.

Patented Feb.1, 1876.

jv. o.

NPERS. PKOTULITHOGRAFHEH, WASHINGTON. D. C,

NITED STATES PATENT OFFICE.

ROBERT J. SHEEHY, OF BOSTON, MASSACHUSETTS.

IMPROVEMENT IN ELECTRIC CLOCKS.

Specification forming part of Letters Patent No. 173,072, dated February l, 1876; application iled November 16, 1875.

To all whom it may concern Be it known that I, ROBERT J. SHEEHY, of Boston, in the county of Sulolk and State of Massachusetts, have made a new and useful Invention having reference to Electric Clocks; and do hereby the same to be fully described in the following specification, and represented in the accompanying drawings, of Which- Figure 1 is a front elevation, and Fig. 2 a rear elevation, ot' a primary and a secondary electric clock, with means by which the secondary clock is operated by the primary one.

By means hereinafter explained, any number of electric clocks like the secondary one may be putin operation from one primary clock.

My invention relates to apparatus for timesounding or signalizing. Also, to the combination ot' an electro-magnet and its armature with an auxiliary armature to operate therewith, substantially as hereinafter explained.

Heretofore, so far as I have been able to learn, it has been customary to move the minute-hand of a secondary electric clock .but once .every minute or halt-minute, such clock, generally speakin g, being without any secondhand or dial to indicate seconds. In my secodary clock, as shown in the drawings, and hereinafter described, there is a second hand and dial to indicate seconds ot time, .and the minute-hand has a movement every second. Furthermore, instead of applying tothe second-hand arbor of the primary clock the apparatus for closing the electric circuit once during each revolution ot' the saidV arbor, I make use of the escapement-whe'el and a spring, duly insulated, to eit'ect the opening and closing of the electric circuit, such enabling me, by imparting to the escapemcntwheel the necessary velocity, to move the second-hand of the secondary clock one or more times a second, as occasion may require, the arbors of the second and minute hands being provided with a train, by which the minutehand arbor is operated from the second-hand arbor.

In the drawings, A denotes the wheel-work of a common clock, in which c is the balancewheel, b the escapement-lever, and c the escapement-wheel: Against the periphery ofthe wheel c there is arranged, as shown, a metallic spring, el, projecting from the lower end ot' a screw, c, that extends up through a metallic ear, j', projecting from an insulator or piece of glass or hard rubber, g, fixed to the frame h of the clock. Two nuts,z' lc, screwed on the screw c, one above and the other belowthe ear f, serve, with such screw, to adjust the spring d relatively to the escapenient-wheel. From the upper end ot' the screw c a wire, l, from one pole of a battery, is attached, and from the frame h another wire, m, is led to the frame n of the secondary clock B, whose second-hand arbor is shown, at o, as provided with a ratchet- Wheel, p, having sixty teeth. With this ratchet-wheel a pawl, q, engages, such pawl being pivoted to a lever, fr, which has fixed to it a small armature, s, arranged immediately over the poles of an electro-magnet, C, more particularly shownin Fig.3, whichisa vertical and transverse section ot' the secondary clock. To the lever r there is an elevating-spring, t, and there is to the frame n an adjustable stop, u, to determine the extent of upward movement of such lever. The second-hand arbor is connected with theminute-hand arbor by a hand arbor will also have a like number ot' movements in such-time. The magnet C is in the circuit of which the wire Z constitutes a part.

From the above it will be seen that during each movement of the escape-wheel lthe circuit will be closed and broken, for while each tooth of the wheel comes into contact with the spring the circuit will be closed, and it will be opened immediately on the tooth passing the end of the spring,in which case the wheel will be wholly out of contact with the spring. This breaking and closing the circuit aids in producing the movement ofthe hands of the secondary clock.

Instead ot' the escapement-wheel to act against the spring, another or circuit breaking and closing wheel may be used ou the arbor of such escapement-wheel.

arm of a lever-hammer, D, of a bell, E, arj ture is somoved. For the slnaller armature to move independently of the larger or upper one, the attractive force of the magnet should be insufficient to move the upper, though sufficient to4 movethe lower, of such armatures.

In order to increase the efficiency of the m agnet, to cause it to operate the larger armature, I use a resistance-coil, Gr, Which is put lin the same circuit With the electro-magnet.

vThe outer Wire y of this coil is attached to the frame of the secondary clock, the inner Wire Z being connected to a spring, I, Which, at one end, is tixed to the frame, but insulated from it by an insulator, K. This spring, supported at its free end against a stud, d', operates with a movable duplex sector, L, that turns and slides on a stationary arbor, a. The upper arc ofthe sector has gear-teeth, to engage with a gear, b4', fixed on the second hand arbor of the secondary clock. The lower arc of thesector is provided With a series of signalizing-teeth, c', to work in succession againsta projection, e', on the spring.

There is applied to the frame a spring, f', to slide the sector L forward on the arbor a', in order to throw the sector out of gear with the wheel b', it being keptin gear by a projection or rider, g', extended down in front of it, and from the frame, as shown.

To the duplex sector there is fixed an overbalance Weight, h, Which, after disengagement of the sector With the gear, which takes place as soon as the upper arc of the sector may have passed by the rider, and the sector is thrown forward on the arbor by the spring, brings the sector in a position for again being coupled with the gear.

From the above it Will be seen that the sector, when in engagement with the gear b', will be revolved by it, so as to carry the signalizingteeth c successively on and oft' the projection e of the spring. When a tooth, c', may be in contact With the projection e', the electric current Will not pass through the resistance-coil, but Will go through the spring and the duplex sector, and thus it becomes relieved of the resistance ot' the coil, so as to increase the attractive force ofthe magnet sufficiently for it to operate the larger armature, and thereby cause the bell to be sounded.

Instead of the resistance-coil an auxiliarybattery may be employed, its Wires being applied, as those ofthe resistance-coil are, to the frame and the spring.

Furthermore, instead of the spring d, insu-v lated and applied to the eseapement-Wheel, as described, I sometimes make use of an equivalent-that is, I insulate one of the escapement-pallets from the rest of the escapements by a piece of glass or hard rubber duly interposed, and connectwith the insulated pallet the circuit-Wire of the battery.

I claiml. The combination of the resistance-coil G, the spring I, the duplex sector L, and its operating gear b with the primary and secondary clocks A B, their electro-magnet C, and its armature S, and the auxiliary armature V, attached to the bell-hammer, all being applied substantially as and to operate as specified.

2. I claim, in combination with the electromagnet C, and its primary armature S, a secondary armature, c, to operate With such magnet and primary armature, substantially as specified.

ROBERT JAMES SHEEHY.

Witnesses R. H. EDDY, J R. SNOW. 

